Supplementary information
18.11 Communication via fault-tolerant S7 connections
CPU 410 Process Automation/CPU 410 SMART
338
System Manual, 05/2017, A5E31622160-AC
18.11.3
Communication between fault-tolerant systems and PCs
Availability
PCs are not fault-tolerant due to their hardware and software characteristics. The availability
of a PC (OS) system and its data management is ensured by means of suitable software
such as WinCC Redundancy.
Communication takes place via fault-tolerant S7 connections.
The "S7-REDCONNECT" software package is required for fault-tolerant communication on a
PC. S7-REDCONNECT is used to connect a PC to a redundant bus system using one or two
CPs. The second CP is merely used to redundantly connect the PC to the bus system and
does not increase the availability of the PC. Always use the latest version of this software.
Only Industrial Ethernet is supported for connecting PC systems. The SIMATIC Net software
V 8.1.2 is required for connection via ISOonTCP. This corresponds to the configuration
TCP/RFC1006 at the PC end.
Note
The PROFINET IO MRP (Media Redundancy Protocol) for PROFINET IO ring topologies is
not supported by SIMATIC NET PC modules. Plant buses as duplex fiber-optic rings cannot
be operated with MRP.
Configuring connections
The PC must be engineered and configured as a SIMATIC PC station. Additional
configuration of fault-tolerant communication is not necessary at the PC end. The connection
configuration is uploaded from the STEP 7 project to the PC station.
You can find out how to use STEP 7 to integrate fault-tolerant S7 communication for a PC
into your OS system in the WinCC documentation.